Stitch-forming mechanism for sewing-machines.



No. 814,642. 7 PATENTED MAR. 6, 1906.

G. A.DEARBORN.

STITCH FORMING MECHANISM FOR SEWING MACHINES.

. APPLICATION FILED SEPT.29, 1904.

3 SHEETS-SHEET 1.

""' HIIIIIIII No. 814,642. PATENTED MAR. 6, 1906. c, A. DEARBORN.

STITCH FORMING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED SEPT. 29, 1904.

3 SHEETS-SHEET 2.

alitoznw No. 814,642. PATENTED MAR. 6, I906.

G.A.DBARBORN.

STITCH FORMING MECHANISM FOR SEWING MACHINES.

' APPLIGATIONYFILEDY SEPT .29, 1904.

3 SHEETSSHBET 3 /J75 m Q awvewtoz thorns snares rarrnnr oi srcn.

CHARLES A. c ansons, or new roan, N. r.

sTarow-Fonram e necessitate cos c. 814;,342. Specification of Letters Patent. Patented March 8, 1906.

Qrigiusl application filed 111;? 21, 1904, Esrial llo. 217,474. Dividadand this application filed September 29, 1M4, Serial No. 228,548,

To all whom; may concern:

Be it known that l, finances DEAR- BORBQE citizen of the United States, and a resident of New York, in the borough. of

Manhattan, county and State of New York, have invented certain new and useful 1m movements in Stitch- Forming Mechanism for Sewing-Machines, of which the following is a specification.

The resent application is a division oi my original application, Serial No. 217,474, filed July 21', 1904, for improvernentsin sewingmachines, and the invention covered by t present case relates to improvements in stitch-forming mechanism w iich are applicable to swung-machines in general, but are particularly designed for overseaming blindstitch sewln -machines, such as illustrated in Patents l 0. 639,669, dated December 19, 1899, No. 679,553, dated July so, 1e01,.NQ.

. 705,325, dated July 22,1902, and No. 705,326

dated July 22, 1902, heretofore granted to me.

In machines covered by my above-named patents the feeding mechanisrnis in the form of intermittently-a0tuated rotating ieed rolls mounted upon a s ring-sustained work suport or frame an engaging the work from eneath and holding'it up against arigid pressenfoot in proper position for the action of the stitch-forming mechanism. y

In the old forms of my machine the needle operating transversely of the line of feed enetrates successive parts of the work, w 'ch. passes over a ridge-forming rib, (also mounted upoii the spring-sustained work support or frame) which in some casesds a part of one of the rotary feed-rolls and in other cases is an independent part projecting between the feed-rolls into engagement with the tin-L der surface of the work. The looper, which cooperates with the needle in the old'forms of my machine, is arranged to be actuated from therear end of the looper-rod by an eccentric universal crank mechanism which imparts to the looper a forward motion on one side of the line of stitchin' ,an axial motion to throw it to the other si e of the line of stitching, a rearward motioii' on the other side of the line of stiching, and finally a 3 second axial motion to throw fitv back to the The looping mechanismcf my improved machine accomplishes the same iir' oses as and improved construction. The improved looper reformed with a sin 1e prong or finger having the necessary, shou ders for engaging and carr ing the loop to take the loop oil of the need e at one side of the line of stitching and carryiniiizt over to the other side of the.

line of stitc g and deliver it again to the needle. The 100 or is adjnstahly mounted in the forward end of the loo er-har, which is formed between its ends wit a journal opening loosely, inclosing a journal-sleeve upon which the looper moves; This j carnal-sleeve is treel journaled-upon a stud projecting laterally cm the free end of a suspended rockarin, wlgch rook-arm is keyed to the end of a rock-s it suitably journa ed in the machinearm and having a connected rock-arm and link at its opposite end, which link extends rearwardly to the main driving-shaft and enages an actnating-eocentric upon said shaft y which the suspended rock-arm supporting the journal-sleeve is given a to-and-i'ro rocking motion for carrying the looper forward and hacktoward and away from the path of the needle. The looper-har has two diametrically cpposite center screws which pass through the walls of the journal opening and are journaled in diametrically opposite sockets formed in the sleeve, By reason of this connection or" the loopercar with the sleeve journaled upon the rockarm it is ossible for the looper to rotatein a vertical'p' ane or move on its pivots in a transverse plane, so

that the looper can move toward and away from the work and transversely to the line of stitchin Unlike the looper mechanism in the old orm of my machine, the forward and back movements of the looper are caused by the movement of the suspended rock-arm,

.which is actuated by the independent -eccentric mechanism just referred to. This suspended rock-arm also 'ves the looper a slight rise and fall in moving orward and backward. For increasing the rise and fall of the looper at'the end of its forward and back strokes and to move thelooper, from one side of the line of stitohii tov the other side of the line of stitching provide an eccentric universal crank mechanism upon the main drivingshaft which actuatesa lateraliyswinging j floating hearing with which the rear end of ism is similar to the same mechanism employed in the old forms of my machine; but in place of directly and positively connecting the rear endof the looper-rod with the said crank mechanism 1 have provided in the new machine a universally-joint ed laterally-swinging floating bearing-frame having a loop at its rear end, through which center screws pass and engage the sleeve our- 'naled upon the eccentric inclined crank-pin,

said floating bearing frame being formed upon its lower edge with two alined soclretbearings in which the cylindrical rear extension of the looper is freely journaled, so as to have free rotary and longitudinal movements therein. By reason of this construction it will be observed that the forward and back movements of the looper are caused entirely by the suspended rock-arm, the looper-rod riding freely in the floating bearing of the guiding crank mechanism justi described, while the inward and outward vibrations of the said floating bearing produced by the rotation of said inclined crank-pin cause the looper to move from one side of the line of stitching to the other.

In order that my invention may be fully understood, 1 will first describe the same with reference to the accompanying drawings and afterward point out the novelty with more particularity in the annexed claims.

In said drawings, Figure 1 is a side elevation of a sewing-machine embodying the improved stitch-forming mechanism. Fig. 2 is a plan view of the same. Fig. 3 is a detail endview, partly in section, of the stitchforming mechanism. Fig. 4 is a detail plan view of the presser-foot. Fig. 5 is a detail sectional plan view'of thefeeding and worksupporting mechanisms. Fig. 6 is a detail sectional elevation showing the support for the feeding-bar. Fig. 7 is a detail side elevation of the looper removed from the looperbar. Fig. 8 is a detail perspective View of the needle-guide.

i The main frame of the machine is formed of a single casting comprising a rigid central base 1, theupwardly-extending rear arm 2, terminating in the sleeves or shaft-bearings 3 4, and a forwardly-extending arm 5, having the needle-shaft bearings 6 7 and the looperrock shaft bearing 3.

10 is the main driving-shaft of the macliine, journaled in the sleeves or bearings 3 4 of'the rear arm 2 and having keyed to one end a driving-pulley Hand fly-wheel 12 and at its opposite end a' crank-disk 13 hereinafter referred to. I

15 is the forwardly-extending needle rockshaft, journaled in the bearings 6 and 7 and having rigidly mounted upon its forward end a needle-carrying rock-arm 16, in which is 65 mounted a curved .needle 17.

18 is I the usual thread-guide and needleclamp mounted upon the rock armlfi by means of the set-screw 19. a

' 20 and 21 are ordinary thread-guides.

Secured to the rear end of the needle rockshaft 15 is a rock-arm 25, having universaljoint connection 26 with a link 27, which encircles an eccentric 28, Y mounted upon. the main power-shaft 10 just inside of the crankdisk 13. The link 27 and the eccentric 28 are formed with spheroidal engaging surfaces to allow free lateral play of (the link in the transmission of the rotary motion of the main shaft 10 into the oscillatory motion of the needle-shaft 15.. By this needle operating mechanism (which is the same as in the prior patents) the needle is given a reciprocatory motion in an arc transverse to the path of the work which is passed through the machine by .the mechanisms now to be described.

Projecting up from the forward edge of the base 1 is an auxiliary arm 30, which is rigidly and adjustably secured to the base by means of set-screws or bolts 31. The auxiliary arm 30 is formed at its'upper end with two sleeves 32 and 33, in which is mounted a pivot-shaft 34, projecting a little beyond each of the sleeves 32 and 33.

34 for holding it rigidly in position.

10 is a horizontal forwardly-extending spring sustained Work supporting frame. This frame has the rearWardly-presented integral journal-sleeves 41, which are journaled upon the projecting ends of the givotshaft 34 and rest snugly against the arnesleeves 32 and 33, by which the Work-support ll) is accurately held in position, said support being allowed to move vertically upon its pivot. Surrounding the pivot-shaft 34 between the sleeves 32 and 33 is a torsionspring 15, one end of which is extended beneath the work-supporting plate 40 to hold said plate upward with a yielding pressure, while the other end 45 of said spring is extended down behind the auxiliary frame-arm 30 and is engaged by a hook 46, formed on the rear end of a threaded rod 47, which passes freely through an opening formed in the arm 30 and is enga ed at its forward threaded end by a butter y-nut 48, by which Set-screws 35 passthrough the -sleeves 32 and 33 and engage the pivot-shaft the tension of the spring 45 can be increased or decreased at will. The work-supported is also formed with an integral downwardltygrojecting arm 41*, extending below the le and bearing 41 in position to engage an adj ustable stop in the form of a screw 19, which fee is threaded through an integral post 50 of the I auxiliary arm 30. By adjusting the screw-f by screws 101 to the forward web portion of a yoke 102, which is formed with rearwardlypresented lugs 103, which are pivoted upon set-screws 104, mounted in the. downwardlyprojecting lug 105, formed integral with the machine-arm 5. a

106 is a torsional spring coiled around a reduced portion or hub of the lug 1'05 and engaging at one end a pin 107 projecting from lug 105 and at its otherend beneath the rocking yoke 102, thereby giving the presser foot a spring tendency to rise away from the Worksupporting plate justdescribed.

The presser-foot is formed with a main longitudinal slot 110, through which the ridge of the work is ressed by the work-sup- 1 porting plates and ridge-forming disk for the operation of the feed and needle, and an auxiliary longitudinal groove 111 to allow for the movement of the looper in moving rear wardly to deliver the loop to the needle.- The presser-foot plate also has asmall perforation 112 to allow for the depression of the needleguide 180 when the needle penetrates the goods and also to receive the lower end of the needle-guide and allow for the elevation of the presser-foot during the feeding stroke.

113 is the transverse needle-groove cut in the upper face of the presser-foot.

The spring 106 acting upon the ivotallymounted presser foot normally ten s to raise the presser-foot away from the work-support. To f rce the presser-foot down against the work on the supporting-plates and disk, I provide a yoke 115, projecting from the upper face of the presser-foot and formed with a central dip, or depression at 1 15, which yoke is engaged by a grooved antifriction-roller 116,

a mounted upon a pin 117, projecting from a short rock-arm 118, journaled upon a lug 1'19, projecting beneath and formed integral with the bearing 6' on the arm 5. The pin 117 also carries an antifriction-roller 120,

which runs upon the peripher of a cam 121, keyed to the forward end of t e needle rockshaft 15 between the bearing 6 and the needle-carrying rock-arm 16. This cam 121 is so positioned upon-the needle rock-shaft that the high portion of the cam will depress rock'- arm 118 and through it the presser-foot just prior to the penetration of the needle into the work, and the low, portion of the cam will allow the presser-foot' to be raised by the'action of its spring just at the commencement of the feeding stroke of the feeding-dog. The

Presser-foot and means foroperating and controlling it are claimed .in my original application, Serial No. 217 ,474, above referred to.

In place of the under roller-feed mechanism heretofore employed in my machine I have arranged an effective reciprocating feeding device, which engages the Work upon its'upper face. This feeding device forms no part of my present application, but is the subject of a copending divisional application, Serial No. 226,547, filed of even date herewith. This device will now be described.

I employ a two-part feed-dog 130 131, each part of which is formed with two parallel rows of serrationsor teeth. on its under surface and arranged to engage the Work in front and in rear of the ath of the needle. This two-part feed-dog 15 preferably formed integral with and projects laterally from a supporting-arm 132, which is secured by means of screws to the forward end of a longitudinally-movable rocking arm or bar 133. This 136, which embraces an eccentric 137, keyed.

to the main driving-shaft 10 of the machine by which the feed mechanism is operated. This eccentric will cause the arm or bar 133 to reciprocate forwardly and backwardly and rock slightly upon its pivot-roller 135 to raise andlower the feed-dog. .The inclined slot 134-, moving over the antifriction-roller 135 during the reciprocation of arm or bar 133, serves to counteract the lifting of the dog on its feeding stroke and increasing the lifting action on its return stroke. The movement of the feed-do under the action of the eccentric as modi ed by the inclined slot and roller-support will be a feeding stroke in a straight line in a horizontal plane and a return stroke in an arc. The two rows of teeth upon the feed-'dog-130 and 131 engage the work in slot 110 of the pressenfoot directly above the independently-yielding work-supporting plates and 75, above referred to.

Freely journaled in the hearing 8 of the machine-arm 5 is 'a rock-shaft 140, carrying at its inner end a depending rock-arm 141, to the lower end of which is pivoted at 142 the forward end of the link 1 13, which is formed at its rear end with a yoke144, embracing an eccentric 145, keved to the main shaft 10. At t f the outer end of the rock-shaft is keyed the the depending rock-arm 146, u on which the looper is j ournaled and by whic the looper is operated. The rock-arm 146 carries at its lower end an outwardly-projecting j'ournal stud 147, which referably has a threaded inner end to provi e a convenient means for attaching-itto the'rock-arm. Freely journaled on the stud 147 is a journal-sleeve 148, 'ch is confined'u on the stud between the rock-arm 146 and t e head of the stud.

150 is the main body portion of the looperrod. This body portion 150 is formed with a central circular opening 151, which loosely surrounds the bearing sleeve 148.; The

100 'er-rod body is pivotally mounted upon sai sleeve by means of the diametrically op-.

posite cone-pointed center screws 152, which are threade through the lower and upper walls of the central portion of the looper-rod body 1 and are seated in diametrically oppo-' site cone-shaped recesses formed in the j ournal-sleeve 148. These center screws 152 are preferabl provided at their outer ends with small -nuts 153 for securing them in the desired adjusted osition in engagenient with the sleeve 148. yreason of the pivotal connection between the looper-rod body and the 'ournal-sleeve 148 it will be observed that looper can be rocked upon its pivots in an approximately horizontal plane in addition to its vertical oscillatory movements 'u on the journal-stud 147, as just described. he loo er-rod body portion 150 is also formed wit an inwardly curved forwardlyrojecting -arm 155 formed at its front end with a socket, which receives the shank of the looper proper, 157, the looper being secured in the soc ret by means 0 set-screw 156 passing throu h suitably threaded ears of the undersp it ortion of the socket. The looper proper is ormed ofa single prong 157, havlng the'thread-engaging shoulder 1 57 and a curved cut-out-or depressed portion 157 behind said shoulder to allow forthe assage of the needle. The 100 errod bo y portion 150 is also formed wit a rearwardly-presented. socketarm 158, into the socket of whichis threaded the forward end of the tail-rod 159.

A locking-nut 160 is also'threaded' upon said tail-rod 159to clamp it in position upon the body portion. I y

As above explained, a crank-disk 13 is mounted upon the end of the driving-shaft 10. This crank-disk 13 has projecting from it at an an le of about forty-five degrees an arm 165, w "ch supportsa crank-pin 166,- extendin "at right angles from the arm Journa ed upon the crank-pin 166 is a sleeve 167 having diametrically op osite coneshaped bearing-sockets, in WhlC are seated the'cone-gointed center screws 169, which are three ed through the side walls of the loop or yoke 170 forpivotally connecting said yoke wlth the journal-sleeve 167. The loop or yoke 176 hasfformed integral with it and plates andthe free y-journaled ridgeextending forwardly from it adjacent to its lower edge a bracket-arm 171 formed with the integral journal-sockets 17 2 in which the guiding tail-rod of the looper is freely journaled, so as to reciprocate longitudinally and oscillate therein. The integral yoke 170, bracket arm 171-, and bearing-sockets 172 constitute what I term a floating bearin for im arting the lateral and a part of the vertica movements to the looper proper, said floating bearing being operated by the universal-joint connection and crank-pin above referred to.

17 5is the usual thread-tension device.

- is a vertically-movable needle-guide formed with an inwardly and forwardlyf curved finger having a needle-groove in its face. The lower end of this needle-guide rests directly above the o ening 112 in the presser-foot and is ada te to intermittently rise and fall into gui ing contact with the needle and away from the needle. This nee-- dle-guide has an upwardly-projecting guidestem 182, which is supported in the integral socket-bearing lugs 119 and' 183 of the sewing-machine arm and carries'an inwardlycurved arm 184, secured to it by screw 185 and projectin over above a controlling-cam I 186, which is eyed to the needle rock-shaft 15 and formed inte ral with the earn 121,

tion of the presser-foot' The spiral spring 187 is confined between the hub of arm 184 and the upperbearing 183-to give the needleguide 180 a normal tendency to move downwardly and holding the arm 184 in contact with the controlling-cam 186.

The operation of'the improved machine may be briefly described as follows: The machine is primarily intended to accom lish what is known 'as overseaming blindstitching work, which style of stitchin is most commonly emplo ed in seamin e lower edges of trousersegs, skirts, an other garments of tubular form. The material to be sewed is first folded at one edge to form a hem of the desired depth and by depressing rid e-forming (118k 60, the turned-up portion or cm of the material (that is, the double ri ht 'ust above the work-su ,ortin late 7 iVhen the pressureis reniiii'ed fr n i the work-supporting frame, said frame returns to its normal horizontal or raised position and causes the ielding .work-sup orting fiirming rib 60 to force a ridge of the material up into. the main longitudinal slot- 110 of the presserfoot 'the disk 60, which engages the work diabove referredto, w ich controls the elevathickness, of the work) being placed to the rectly beneath the turned-over edge of the hem, forcing the material directly above it slightly beyond the parts of the material supreturn movement in withdrawing from the.

ported by the yielding plates. The needle oscillating transversely of the line of feed penetrates the raised portion or ridge of the material justabove the rib 67 at one side and passes through the material supported on the ridge-forming disk 60 and emerges at a point ]ust above the plate 75 and carries the loop of the thread to the right of the point from which the needle emerges. As the needle starts to return through the material the looper moving forward on the right-hand side of the line of stitching takes the loop from the needle and while the needle is completing its material carries the loop across the line of stitching to the left and startsto recede and move downwardly to present the loop in open position directly in the path of the needle, which at the proper-moment again moves forwardly, entering the loop and again piercing the'material, as just explained, for another stitch, which is accomplished in the same manner. While the looper is moving across the line of stitching from right to left to present the loop to the needlelthe presser-foot is raised from the work-sup orting plates and the feed-dog is given its fzaedingstroke, the material bein freed from the pressureof the presser-foot furing the time that the feeddog is making its active stroke. Immediatel after the completion of "the working stro e of the feed-dog the .presser-foot is again clam ed securely upon the material to hold it firm y while the needle penetrates the work. After the looper has delivered the loop to the needle it isimoved from the lefthand side of the line of stitching over to the right-hand side of the line of stitching in readiness for another forward stroke, as explained, and during this same time the feeddog is making its return stroke outofengagement with the work in readiness for another feeding stroke. As the needle starts forward to penetrate the material theneedle-guide is raised by its cam, so that the grooved guiding-finger engages and guides the needle until its point has completely penetrated the work, when the needle-guide is automatically lowered out of contact with the needle by the action of its sprin when released by the cam to allow the nee e rock-arm to accomplish its full upward stroke.

As stated above, the forward and backward movements of the looper and partly its vertical vibration are caused by the oscillations of the'suspended rock-arm, on which the looper-body is journaled, while the transverse movements of the looper from one side of the line of stitching to the other and partly the vertical vibrations are caused by the laterally-swinging floating bearing actuated by theeccentric crank mechanism.

vHaving thus described my invention, the following is'what I claimas new therein and desire to secure by Letters Patent:

looper, substantially asset forth.

1. In a sewing-machine, the combination with suitable stitch-forming mechanism including a needle, means for supporting the work which is to be'operated upon, a suitable feed device, a reciprocating stem carrying a needle-guide and having lifting means, bearings in which said stem is mounted, a spring arranged to lower the stem so as to move the needle-guide away from the needle, and acam arranged to engage said lifting means 7 '5 and intermittently raise the stem, so as to move the needle-guide into guiding position.

2. In a sewing-machine, .the combination with suitable stitch-forming mechanism, including-a-needle, means for sup orting'the work to be operated upon, a suita le feed device, a vertically-reciprocating needle-guide, bearings in which said needle-guide is mounted, an arm mounted upon the needle-guide, an oscillatory cam engaging said arm for raising the guide into active position, and a spring, engaging the needle-guide for lowering it into inactive position under the control of the cam, substantially as set forth.

3. In a sewing-machine, the combination with a work-sup ort, a suitable feeddevice, and a needle, of a looperbar carrying a looper atits forward end and a guide-rod at its rear end, a suspended rock-arm on which the loo er-bar is journaled, means for actuating t e rock-arm for imparting forward and backward movement to the looper, and

a bearing-frame movable laterally and up and down, the guide-rod of the looper-bar being journaled in the bearing-frame and by which the looper is made to move laterally and u and down, substantially as set forth.

4. a sewing-machine, the combination with a suitable support for work, a suitable feed device, and a needle, of a looper-bar carrying a looper at its forward end and a guiderod at its rear end, a suspended rock-arm on which the looper-bar is journaled, means for operating said rock-arm for imparting forward and backward movements to the looper, an eccentric crank mechanism, and a laterally swinging floating bearing havin universal-joint connection with said cran mechanism'and bearings engaging the guiderod of the looper, substantially as set forth. 1 15 5. In a sewing-machine, the combination of a suitable support for work, a suitable IOS feed device, and a needle and operating mechanism, with a-looperbar carrying a looper at its forward end and. a guide-rod at its rear end, a suspended rock-arm carrying a stud, a sleeve freely journaled upon said stud, an o ening formed through the looperbar and lbosely surrounding said sleeve, center screws passing through the looperbody and seated in the sleeve, means for operating said suspended rock-arm, and a laterally-swinging floating bearing having bearings which engage the guide rod of the 6. In a sewing-machine, the combination I feeddevice, and a needle, of aflooper-bar carwith a suitable support for work, a suitable feed device, and a needle, of a looper-bar carrying a looper at its forward end and a guiderod at its rear end, a suspended rock-arm carrying a stud, a sleeve freely journaled u on; said stud, an opening formed through t e looper-bar and loosely surrounding said sleeve, center screws passing through the looper-body and seated in the sleeve, a rockshaft upon which saidsuspended rock-arm is mounted, means for operating said rockshaft, eccentric crank mechanism, and a laterally-swinging floating bearing having universal joint connection with said crank mechanism and'forrned with bearings which engage the guide-rod of the looper, substan- I I tially as set forth.

7. In a sewing-machine, the combination with a suitable support for work, a suitable rying a looper at its forward end and a guiderod at its rear end, a suspended rock-arm on which'the loo er-bar is journaled, means for operating sai rock-arm for imparting forward and backward movements to the looper, an eccentric crank mechanism, in cluding an inclined crank p in, a laterallyswinging floating bearin comprising a loop or' yoke surrounding sai crank-pin and having universal-joint connection therewith, and alined bearing-sockets integral with said loop or yoke, the guide-rod of the looper-bar being freely journaled in said alined bearing- 1 sockets, substantially as set forth.

CHARLES A. DEARBORN.

Witnesses:

WILLIAM P. HAMMOND WM. E. KNIGHT 

